This study investigates the effect of design-based science (DBS) instruction on students' learning of electrical energy and students' metacognitive strategy use in science. Two classes of seventh-grade students participated in the study. DBS instruction was used in the treatment group, while the comparison group was taught the unit with curriculum-oriented science instruction (COSI). Mixed between/within subjects, ANOVA results suggest that at the beginning of the study, there was no difference between the treatment and comparison groups in terms of electrical energy learning or metacognitive self-regulation. At the end of the study, students in the DBS group outperformed students in the COSI group in electrical energy learning. Students in both groups had increased understanding of electrical energy; however, the improvement levels were much higher in the DBS group than in the COSI group. At the end of the study, the DBS group also reported higher levels of monitoring strategy use than the COSI group, while there was no difference between the groups in terms of planning and regulation strategies. Furthermore, the DBS group showed improvement in all metacognitive learning strategy components, whereas no change was detected in the COSI group. Thus, it seems that DBS contributed to students' learning in electrical energy and enhanced their metacognitive self-regulation in science more than COSI. Additionally, students in the DBS group generally thought positively about the influences of DBS instruction on their science learning. They identified similarities between DBS processes and activities engineers use in real life.